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Related papers: Does the Universe Accelerate Equally in all Direct…

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The kinematics and dynamic interpretation of the cosmological expansion is reviewed in a widely accessible manner with emphasis on the acceleration aspect. Virtually all the approaches that can in principle account for the accelerated…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-19 Yu. L. Bolotin , O. A. Lemets , D. A. Yerokhin

A kinematic method to access cosmic acceleration based exclusively on the Sunyaev-Zel'dovich effect (SZE) and X-ray surface brightness data from galaxy clusters is proposed. By using the SZE/X-ray data from 38 galaxy clusters [Bonament et…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-19 J. A. S. Lima , R. F. L. Holanda , J. V. Cunha

Supernova remnants are believed to be a major source of cosmic-rays in the Galaxy. As their progenitors are commonly found clustered in OB associations, one has to consider the possibility of collective effects in the acceleration process.…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Gilles Ferrand , Alexandre Marcowith

Recent astronomical observations of SNIa, CMB, as well as BAO in the Sloan Digital Sky Survey, suggest that the current Universe has entered a stage of an accelerated expansion with the transition redshift at $z \simeq 0.5$. While the…

Astrophysics · Physics 2010-11-11 Aleksandra Kurek , Marek Szydlowski

We test the present expansion of the universe using supernova type Ia data without making any assumptions about the matter and energy content of the universe or about the parameterization of the deceleration parameter. We assume the…

Astrophysics · Physics 2009-06-23 Marina Seikel , Dominik J. Schwarz

The observation that Type Ia supernovae are fainter than expected given their red shifts has led to the conclusion that the expansion of the universe is accelerating. The widely accepted hypothesis is that this acceleration is caused by a…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-09 Rutger Dungan , Harrison B. Prosper

In a recent paper \cite{Artymowski:2020zwy} we suggested the possibility that the present acceleration of the Universe is due to thermodynamical behavior of unparticles. The model is free of scalar fields, modified gravity, a Cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-19 Michał Artymowski , Ido Ben-Dayan , Utkarsh Kumar

In this talk, I argue that the method of analysing the m-z data of Type Ia Supernovae (SNe Ia) by assuming exotic energy densities with strange equations of state is misleading and the reasonable remaining option is to make a…

Astrophysics · Physics 2009-05-27 Moncy V. John

Cosmic acceleration is explained quantitatively, as an apparent effect due to gravitational energy differences that arise in the decoupling of bound systems from the global expansion of the universe. "Dark energy" is a misidentification of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 David L. Wiltshire

The accelerated expansion of the Universe measured by high redshift Type Ia Supernovae observations is explained using the non-equilibrium dynamics of naturally soft boson fields. Spinodal instabilities inevitably present in such systems…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. Cormier , R. Holman

The acceleration of the expansion of the universe, ascribed to a dark energy, is one of the most intriguing discoveries in science. In addition to precise, systematics controlled data, clear, robust interpretation of the observations is…

Astrophysics · Physics 2009-11-10 Eric V. Linder

Type Ia supernovae are currently the best known standard candles at cosmological distances. In addition to providing a powerful probe of dark energy they are an ideal source of information about the peculiar velocity field of the local…

Astrophysics · Physics 2009-06-23 Steen Hannestad , Troels Haugboelle , Bjarne Thomsen

Upcoming imaging surveys such as the Large Synoptic Survey Telescope will repeatedly scan large areas of sky and have the potential to yield million-supernova catalogs. Type Ia supernovae are excellent standard candles and will provide…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-25 Suman Bhattacharya , Arthur Kosowsky , Jeffrey A. Newman , Andrew R. Zentner

A phenomenological formalism is presented in which the apparent acceleration of the universe is generated by large-scale structure formation, thus eliminating the coincidence and magnitude fine-tuning problems of the Cosmological Constant…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-14 Brett Bochner

Type Ia supernovae luminosities can be corrected to render them useful as standard candles able to probe the expansion history of the universe. This technique was successful applied to discover the present acceleration of the universe. As…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Xiangcun Meng , Yan Gao , Zhanwen Han

We review the use of Type Ia supernovae for cosmological distance determinations. Low-redshift SNe Ia (z < 0.1) demonstrate that the Hubble expansion is linear, that H_0 = 65 +/- 2 (statistical) km/s/Mpc, and that the properties of dust in…

Astrophysics · Physics 2009-10-31 A. V. Filippenko , A. G. Riess

Type Ia supernovae (SNe Ia) were instrumental in establishing the acceleration of the universe's expansion. By virtue of their combination of distance reach, precision, and prevalence, they continue to provide key cosmological constraints,…

The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of "dark energy" with exotic physical properties, or that Einstein's theory of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 David H. Weinberg , Michael J. Mortonson , Daniel J. Eisenstein , Christopher Hirata , Adam G. Riess , Eduardo Rozo

The standard cosmology strongly relies upon the Cosmological Principle, which consists on the hypotheses of large scale isotropy and homogeneity of the Universe. Testing these assumptions is, therefore, crucial to determining if there are…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-27 U. Andrade , C. A. P. Bengaly , J. S. Alcaniz , B. Santos

Evidence for an accelerated expansion of the universe as it has been revealed ten years ago by the Hubble diagram of distant type Ia supernovae represents one of the major modern revolutions for fundamental physics and cosmology. It is yet…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Alain Blanchard